Speckle filtering

I want to know the references for refined lee and lee sigma filter. As per the information from previous threads, I got that Lee sigma filter is improved lee sigma filter - “Lee J S, Wen J H, Ainsworth T L, et al. Improved Sigma filter for speckle filtering of SAR imagery. IEEE Transactions on Geoscience Remote Sensing 2009; 47(1): 202-213.”
But for refined lee filter - why window size is fixed -7x7 and which reference is used for that filter?
Is it the paper - “Lee J S, Refined Filtering of Image Noise Using Local Statistics, Computer Graphics and image processing 1981, 15: 380-389.”

Please specify. Speckle filtering results of refined lee filter is worse than other filters on my dataset. Is it possible?

Thanks,

a topic for this issue was already opened here: Speckle filtering with Lee filters
Please use it for further discussion.